use strict;
use warnings;
use Tk;
use Tk::JPEG;
use GD;

my $file = $ARGV[0];
my $mw  = MainWindow->new();
my $ww = $mw->screenwidth;
my $wh = $mw->screenheight;

my $imgd = GD::Image->newFromJpeg($file);
my ($iw, $ih) = $imgd->getBounds();
my $imtk;
if ($iw > $ww or $ih > $wh) {
    my $wratio = $ww / $iw;
    my $ratio  = $wh / $ih;
    $ratio = $wratio if $wratio < $ratio;
    $imgd->copyResampled($imgd, 0, 0, 0, 0, $iw * $ratio, $ih * $ratio, $iw, $ih);
    $imtk = $mw->Photo(-data => $imgd->jpeg(), -format => 'jpeg');
} else {
    $imtk = $mw->Photo(-file => $file,         -format => 'jpeg');
}

$mw->Label(-image => $imtk)->pack(-expand => 1, -fill => 'both');
$mw->update;
MainLoop;